This article examines the construction of climate change as a security threat under authoritarian political structures. Based on 55 Vietnamese government policies, strategies, laws, and action plans and building on the theoretical framework of authoritarian environmentalism, the article demonstrates that climate change is increasingly being taken seriously by the Vietnamese policymakers and that security framings play a significant role in this debate. Although the authoritarian state in Vietnam appears to be relatively independent of public preferences and is argued to rely primarily on top-down, non-participatory environmental management, it nonetheless strives to construct narratives that support its public legitimacy. Through the use of various frames such as natural resource security, water resource security, food security, and energy security, Vietnamese discourse presumes that climate change policies should bring economic benefits, which in turn provides the basis for the public security agenda and ultimately serves regime security, strengthening the legitimacy and resilience of the Communist Party of Vietnam. These findings indicate that development and security discourses in the area of climate policy actively interact and perpetuate each other, highlighting an important feature of emerging state environmentalism in Vietnam.